Hi,
I experience some stange behaviour on multi-core node of our cluster that I presume is linked to openmpi. When running for a long time, and several pseudo-nodes of a single multicore node are concerned, one process freezes in a uninterrutible mode (D status) and the others seem to wait for a long time (S status). Concurrent processes over the the other pseudo-nodes are also frozen in D mode. When forcing the sleeping processes to sleep (kill -STOP), normal activity of other processes is recovered. When interrupting blocked process at wakeup, it seems to be blocked in poll_dispatch method, and I guess that comment about multithread must be concerned. Do you know more about this behaviour ? Thank a lot, Lionel Nb : I'm using openmpi v1.3 on Linux debian etch distribution nodes are as following (/proc/cpuinfo): rocessor : 0 vendor_id : GenuineIntel cpu family : 6 model : 23 model name : Intel(R) Xeon(R) CPU E5440 @ 2.83GHz stepping : 10 cpu MHz : 2833.422 cache size : 6144 KB physical id : 0 siblings : 4 core id : 0 cpu cores : 4 apicid : 0 initial apicid : 0 fpu : yes fpu_exception : yes cpuid level : 13 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfm on pebs bts rep_good nopl pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr dca sse4_1 lahf_lm bogomips : 5666.84 clflush size : 64 cache_alignment : 64 address sizes : 38 bits physical, 48 bits virtual power management: .... -- Lionel CHAILAN ASSYSTEM Manager Technique Groupe Calcul Scientifique de PERTUIS lchai...@assystem.com // 06.73.08.85.69